947 research outputs found
Adsorption of Self-Assembled Rigid Rods on Two-Dimensional Lattices
Monte Carlo (MC) simulations have been carried out to study the adsorption on
square and triangular lattices of particles with two bonding sites that, by
decreasing temperature or increasing density, polymerize reversibly into chains
with a discrete number of allowed directions and, at the same time, undergo a
continuous isotropic-nematic (IN) transition. The process has been monitored by
following the behavior of the adsorption isotherms for different values of
lateral interaction energy/temperature. The numerical data were compared with
mean-field analytical predictions and exact functions for noninteracting and 1D
systems. The obtained results revealed the existence of three adsorption
regimes in temperature. (1) At high temperatures, above the critical one
characterizing the IN transition at full coverage Tc(\theta=1), the particles
are distributed at random on the surface and the adlayer behaves as a
noninteracting 2D system. (2) At very low temperatures, the asymmetric monomers
adsorb forming chains over almost the entire range of coverage, and the
adsorption process behaves as a 1D problem. (3) In the intermediate regime, the
system exhibits a mixed regime and the filling of the lattice proceeds
according to two different processes. In the first stage, the monomers adsorb
isotropically on the lattice until the IN transition occurs in the system and,
from this point, particles adsorb forming chains so that the adlayer behaves as
a 1D fluid. The two adsorption processes are present in the adsorption
isotherms, and a marked singularity can be observed that separates both
regimes. Thus, the adsorption isotherms appear as sensitive quantities with
respect to the IN phase transition, allowing us (i) to reproduce the phase
diagram of the system for square lattices and (ii) to obtain an accurate
determination of the phase diagram for triangular lattices.Comment: Langmuir, 201
Critical behavior of self-assembled rigid rods on triangular and honeycomb lattices
Using Monte Carlo simulations and finite-size scaling analysis, the critical
behavior of self-assembled rigid rods on triangular and honeycomb lattices at
intermediate density has been studied. The system is composed of monomers with
two attractive (sticky) poles that, by decreasing temperature or increasing
density, polymerize reversibly into chains with three allowed directions and,
at the same time, undergo a continuous isotropic-nematic (IN) transition. The
determination of the critical exponents, along with the behavior of Binder
cumulants, indicate that the IN transition belongs to the q=1 Potts
universality class.Comment: 6 pages, 5 figure
La influencia del examen de selectividad en la enseñanza, (Análisis de una experiencia en Matemáticas de COU)
Mediante el diseño de dos pruebas - prueba objetiva y ensayo- estudiamos, de forma experimental y utilizando patrones estadísticos lineales, la influencia en las notas finales de la asignatura matemáticas en COU, que podría tener la prueba de acceso a la universidad. Los objetivos educativos desempeñan un papel esencial
Las historias de vida en la formación inicial del profesorado de educación física
En este trabajo se plantea la utilización de las ¿Historias de Vida¿ en la Formación del Profesorado de Educación Física como punto de partida en el desarrollo de procesos de formación del profesorado reflexivos y críticos. En un primer apartado realizamos una revisión sobre el estado de la cuestión a partir de los trabajos realizados en nuestro área curricular. En un segundo apartado explicamos como las historias de vida sirven como técnica de introspección y toma de conciencia de sus creencias y planteamientos sobre Educación Física Escolar. En este sentido la utilización de historias de vida en la Formación Inicial del Profesorado de Educación Física es extraordinariamente interesante como punto de partida a la hora de comprender mejor el sentido de las diferentes asignaturas y la necesidad de ir elaborando sus propios modelos como profesores de Educación Física
Perception questionnaire of teaching competences in Physical Education
La incorporación de las competencias en la universidad española es un elemento clave de su calidad. Sin embargo, no se dispone de instrumentos adecuados ni suficientes para su medida en el campo concreto de la formación inicial del profesorado de Educación Física. El principal objetivo de este trabajo es diseñar y validar una escala para medir la percepción de competencias docentes de este alumnado. Para su construcción y validación, se ha seguido una metodología fundamentada en la Teoría Clásica de Test incidiendo especialmente en el cálculo de la fiabilidad y de la validez de la escala. La muestra para su validación es de 1713 estudiantes y egresados (1240 estudiantes, 473 egresados), pertenecientes a 20 universidades españolas. La escala final presenta una
estructura factorial de cuatro factores principales y 22 ítems con los que se alcanza una alta fiabilidad y una adecuada validez de contenido y de constructoThe incorporation of competences in Spain is a key element of its quality. However, there are no instruments available to measure them in the specific field of Physical Education Teacher Education. The main objective of this study is to design and validate a scale to measure the perception of the teaching competences of these students. For its construction and validation, a methodology based on the Theory of the Classic Test was followed, with special emphasis on the calculation of the reliability and validity of the scale. The sample for its validation is 1713 students and graduates (1240 students, 473 graduates), belonging to 20 Spanish universities. The final scale presents a factorial structure of four main factors and 22 items with which high reliability and adequate content and construct validity are achievedEste estudio se ha llevado a cabo dentro del proyecto de I+D+i: “La competencias docentes en la formación inicial del profesorado de educación física”. Convocatoria de noviembre de 2013 del Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad, en el marco del Plan Estatal de Investigación Científica y Técnica y de Innovación 2014-2017. Referencia: EDU 2013-42024-R. Duración: 3 años (2014-2017
Action-Research, Professional Development of the Physical Education Teachers in Rural Schools
La finalidad de este estudio es analizar la influencia de un grupo de trabajo de Investigación-Acción en el desarrollo profesional de maestros de Educación Física (EF) que ejercen su labor docente en la Escuela Rural.
El diseño es un estudio multicaso. Para la recogida de datos se utilizaron: historias de vida, entrevistas en profundidad, análisis de documentos y diario de investigación. El análisis de datos se realizó a través de un proceso de categorización.
Los resultados muestran que: (a)-los maestros de EF que ejercen su labor docente en la escuela rural pasan por situaciones difíciles y complicadas los primeros años, y que la pertenencia a grupos de Investigación-Acción les
ayuda a que la adaptación a este contexto educativo sea más rápida y fácil; (b)-la metodología de Investigación-Acción genera procesos de reflexión que ayudan a mejorar su práctica docente, influye positivamente en su desarrollo profesional y supone un apoyo.The purpose of this paper is to analyze the influence of a Action Research group on professional development of physical education (PE) teachers in rural school. The research methodology used was case study. Data collection was conducted through interviews, life stories, document analysis and research notebook. Data analysis was performed through a categorization process.
The results show that: (a)-PEF teachers in rural school engaged in difficult situations at early years, and to be a membership of Action Research group helps them adapt to this context educational faster and easier, (b)-the Action Research methodology generates reflective processes that help improve their teaching, has a positive influence on their professional development and represent a suppor
Positive Psychology: Supervisor Leadership in Organizational Citizenship Behaviors in Nurses
Introduction: In nursing, identifying factors encouraging positive work attitudes is ex-tremely important since a nurse’s performance directly impacts the quality of the care they provide, and, therefore, their patients’ health. Objective: The main objective of this research is to analyze whether the supervisor–nurse relationship is positively correlated with a nurse’s organizational citizenship behaviors. Thus, we established a main hypothesis as follows: the quality of the supervi-sor–nurse interpersonal relationship is positively related to the job satisfaction of the nurse, controlled by moderating the effects of psychological empowerment, the perceived organizational sup-port, and leader–leader exchange. Methodology: This is a cross-sectional descriptive study with individuals as the units of analysis. The population studied comprised all the nurses and supervisors working in nine public hospitals in the autonomous community of Aragon (Spain). The sample con-sisted of 2541 nurses, 192 supervisors, and 2500 paired dyads. Self-report questionnaires were used to ensure workers’ anonymity. The dependent variable was the nurse’s organizational citizenship behaviors; the main independent variable was the supervisor’s leadership; the moderating variables were the nurse’s empowerment, the organizational support the nurse perceived, and the quality of the supervisor–superior relationship. Results: Empirical evidence demonstrates that the quality of the supervisor–nurse relationship is positively correlated with organizational citizenship behaviors. The results also confirm the moderating effect of nurses’ empowerment and of the organizational support they perceive. Discussion: Our research shows how important it is for organizations to es-tablish management practices promoting high-quality nurse–supervisor relationships; thus, hospital management should monitor both the supervisors’ performance and leadership. Conclusions: The quality of the relationship the supervisor establishes with their nurses is vitally important since it is a necessary requirement for beneficial results for the organization as a result of citizenship behavior practice
Modeling Noisiness to Recognize Named Entities using Multitask Neural Networks on Social Media
Recognizing named entities in a document is a key task in many NLP
applications. Although current state-of-the-art approaches to this task reach a
high performance on clean text (e.g. newswire genres), those algorithms
dramatically degrade when they are moved to noisy environments such as social
media domains. We present two systems that address the challenges of processing
social media data using character-level phonetics and phonology, word
embeddings, and Part-of-Speech tags as features. The first model is a multitask
end-to-end Bidirectional Long Short-Term Memory (BLSTM)-Conditional Random
Field (CRF) network whose output layer contains two CRF classifiers. The second
model uses a multitask BLSTM network as feature extractor that transfers the
learning to a CRF classifier for the final prediction. Our systems outperform
the current F1 scores of the state of the art on the Workshop on Noisy
User-generated Text 2017 dataset by 2.45% and 3.69%, establishing a more
suitable approach for social media environments.Comment: NAACL 201
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